Unintentional hazardous substances-related hospitalisations

This section presents information on hospital discharge events from unintentional hazardous substances-related injuries in New Zealand. This factsheet uses data from the National Minimum Dataset from 2001 to 2020.

Each year, many people in New Zealand are injured from exposures to hazardous substances, which are often preventable (World Health Organisation 2004). Chemical contamination of the environment can harm people’s health and the environment. For example, misusing pesticides and aerial spraying with insecticides can damage the ecosystem. Hazardous substances can be widely and unsafely used, such as petrol being inappropriately stored in unlabelled drinking water bottles. Industrial workers may poorly handle large volumes of chemicals, which can be extremely dangerous. A growing number of chemicals are used around the home. If they are not used or stored properly, this could lead to hazardous substances-related injuries.

Acute health effects from exposure to a hazardous substance are diverse and include headache, nausea and vomiting, skin corrosion and burns. Chronic health effects include asthma, dermatitis, nerve damage, and cancer (MBIE 2013).

Documents

Factsheet: Unintentional hazardous substances-related hospitalisations (Nov 2021) Download report PDF
Metadata: Unintentional hazardous substances-related hospitalisations Download report PDF

In 2020, there were 419 hospitalisations for unintentional hazardous substances-related injuries out of a total of 678 hazardous substances-related hospitalisations.

The age-standardised rate for unintentional hazardous substances-related injuries decreased significantly from 13.8 per 100,000 (503 hospitalisations) in 2001 to 8.9 per 100,000 (419 hospitalisations) in 2020. This drop was primarily driven by a decrease in the rate for males. The rate for males was at least twice the rate for females since 2001.

Figure 1: Unintentional hazardous substances-related hospitalisations, by sex, 2001–20

Children under five years continued to have the highest hospitalisation rates since 2001

In 2020, the hospitalisation rate continued to be the highest for children under five years at 23.6 per 100,000 (72 hospitalisations), despite a statistically significant decreasing trend since 2001 (Figure 2). Several factors likely contribute to the risk of exposure in this age group. These include:

  • the appeal to children of the colour, shape, taste, smell or presentation of some chemical products
  • a large amount of time spent in the home
  • newfound mobility
  • an inability to recognise potential danger and
  • desire to put things in their mouths (Kamboj et al 2019)

Figure 2: Unintentional hazardous substances-related hospitalisations, by age group, 2001–20

 

Children in the 0–4 year age group have the highest hospitalisation rates for ‘Other and unspecified chemicals and noxious substances’, ‘Organic solvents and halogenated hydrocarbons and their vapours’ and ‘Pesticides’

There were marked differences in the age-specific rates in the hazardous substances-related hospitalisations during the period of 2001–20. Children in the 04 year age group have the highest hospitalisation rates caused by ‘Other and unspecified chemicals and noxious substances’ since 200105 (Figure 3a).

Figure 3a:Unintentional hospitalisation for ‘Other and unspecified chemicals and noxious substances’ (ICD 10=X49), by age group, 2001–20

Children in the 04 year age group are disproportionately affected by injuries from ‘Organic solvents and halogenated hydrocarbons and their vapours’. In 201620, they had a rate of 5.3 per 100,000 (81 hospitalisations) (Figure 3b). The rate for this age group decreased between 200105 and 201620, but the rate for other age groups remained stable between these periods.

Figure 3b: Unintentional hospitalisation for ‘Organic solvents and halogenated hydrocarbons and their vapours’ (ICD=X46), by age group, 2001–20

Children in the 04 year age group are also more at risk from ‘Pesticides’ injuries, they have the highest hospitalisation rates than other age groups, despite a statistically significant general downward trend since 2001-05 (Figure 3c).

Figure 3c: Unintentional hospitalisation for ‘Pesticides’ (ICD 10=X48), by age group, 2001–20

The top three substances/substance categories resulting hospitalisation in 2020 were chemical and noxious substances, petrol, corrosive substances and other gases

In 2020, the top three substances/substance categories resulting in hospitalisations for unintentional hazardous substances exposures were chemical and noxious substances, petrol, corrosive substances and other gases (Figure 4).

Figure 4: Top 15 substances/substance categories resulting in hospitalisation following unintentional exposures, 2020

Māori had a higher hospitalisation rate than non-Māori in 2020

In 2020, the hospitalisation rate for hazardous substances-related injuries for Māori was 12.1 per 100,000 (101 hospitalisations), higher than the rate for non-Māori (8.2 per 100,000; 317 hospitalisations).

When the non-Māori data are further sub-divided into ‘Pacific’, ‘Asian’ and ‘European/Other’ ethnic groups, the rate for the European/Other group decreased between 2001 and 2020, but the rate for Māori has not changed during this period (Figure 5).

The rates for Asians were suppressed in 2001, 2003, 2004, 2006 and 2007 due to low numbers (<20) of hospitalisations. Asians had the lowest hospitalisation rate in 2001, 2005 and 2008 onwards.   

Figure 5: Hospitalisations related to hazardous substances, by ethnicity, 2001–20 (age-standardised rate per 100,000)

People living in the most deprived areas (NZDep 2018 quintile 5) have a higher hospitalisation rate than those in the least deprived areas in 2020

In 2020, the hazardous substances-related hospitalisation rate was higher in the most deprived areas (NZDep 2018) than in the least deprived areas (Figure 6)

Figure 6: Unintentional hazardous substances-related hospitalisations, by NZDep2018 quintiles, 2020 (age-standardised rate per 100,000)

In 2011–20, people living in the West Coast DHB had the highest rate of hazardous substances-related hospitalisations (19.9 per 100,000; 58 hospitalisations). The lowest rate was in the Capital & Coast DHB (5.7 per 100,000;170 hospitalisations) (Figure 7).

Even though some DHBs with small populations such as West Coast and Whanganui have high rates of hospitalisation, the number of hospitalisations is small. This is in contrast to larger population regions such as Capital & Coast and Canterbury DHBs, which have many hospitalisations but low hospitalisation rates.

Figure 7: Unintentional hazardous substances-related hospitalisations, by DHB, 2011–20 (age-standardised rate per 100,000)

Information about the data

This indicator reports unintentional hazardous substances-related hospital discharges using data from 2001 onwards. This indicator is an analysis of the most recent data available from the National Minimum Dataset, provided to EHINZ by the Ministry of Health in August 2021. Data has been pooled to give sufficient numbers for analysis where appropriate. For more information on the list of ICD-10 that are covered in this analysis, see metadata.

Most hazardous substances injuries are considered acute (short-term, intense exposure) rather than chronic (prolonged low intensity exposure) events. Chronic harm from hazardous substances is hard to measure because it is often difficult to determine what caused the harm. This means that data on chronic harm is hard to find and likely to underestimate the number of people affected.

References

1. Kamboj A, Spiller H A, Casavant M J, et al. 2019. Household cleaning product-related ocular exposures reported to the United States poison control centres. URL: https://doi.org/10.1038/s41433-019-0691-9 (Accessed November 2021)

2. Ministry for Business, Innovation, and Employment. 2013. Work-related disease in New Zealand. Wellington. New Zealand.

3. ESR. 2013. World Health Organisation. 2004. Guidelines on the prevention of toxic exposures. URL: https://www.who.int/ipcs/features/prevention_guidelines.pdf (Accessed November 2021)

Downloads Useful links Back to Top